The period of the Tang dynasty (618-907) became the high point of economic prosperity and political power of the Chinese empire, and had a deep and many-sided influence upon the following history of many of the states and peoples of Asia. At that time the Chinese empire implemented to the largest scale her geopolitical potential. The political influence of China spread over great amounts of territory from Korea to Persia and from Vietnam to the Tianshan mountains. Thus the Chinese system of political and legal regulation was also imposed over a vast region of Central Asia.

In the traditional Chinese ideology, a mono-centric political concept of the universe reigned over by the emperor of All under Heaven (Tianxia), determined the character of both the foreign relations and the international doctrine of China. The desire of the Chinese emperors to civilize and to protect the neighboring peoples, who were supposed to be seeking their support, was a strategy for real unification. The Chinese ruler's functions of dividing and organizing the universe were connected with his individual sacred power. According to the traditional world-view, the ruler's sacred power had a wholesome effect not only on the Chinese people, but also on the “distant” peoples, who could voluntary submit and come with tribute to the imperial court. All the peoples and tribes, living at different distance outside China were considered to be actual, or potential vassals of China. Meanwhile the practical principles of Chinese traditional foreign policy were never reduced to a simple dichotomy of “civilization – barbarism”.

China used flexible methods in diplomacy, had a many-staged system of patrimonial vassalage, and thus a very large capacity for geopolitical multi-faceted creative work. Official ideology explained all the imperial actions aimed at establishing control over the new territories by the need to patronize the ethnical periphery, or to punish neighboring tribes who had breached their obligations as vassals…